Gravity Modeling Environment (GME)

The package consists of tools to aid in the fast, flexible, and robust estimation of gravity models using modern, best practices. It offers several distinct advantages over alternative software choices for conducting gravity analysis. First, the package is written in Python, a flexible, powerful, and free programming language that can be readily used on a wide variety of computers with no cost. Second, unlike more general statistical software, which must cater to a broad number of needs, the GME package has been specifically designed to perform gravity analysis well. Third, because the tools are implemented in Python, users have access to an enormous and growing collection of third-party tools to incorporate into and expand their work. In the current release, the GME package performs Poisson Pseudo-Maximum Likelihood (PPML) estimation at the industry level, including all the necessary diagnostics. The package also includes a set of tools for producing summary statistics and other types of commonly sought descriptive information. The package can save and load estimation results in full or using a space-saving slim results option.本工具包提供一系列工具，助力依托现代最佳实践，快速、灵活且稳健地开展引力模型（gravity models）估计工作。相较于其他用于引力分析的软件工具，本工具包具备多项独特优势。其一，本工具包基于Python编程语言编写——这是一门灵活、强大且开源免费的编程语言，可在各类计算机上无成本部署使用。其二，相较于需兼顾多元应用场景的通用统计软件，GME工具包专为优化引力分析性能量身打造。其三，依托Python的丰富生态，用户可调用规模庞大且持续扩容的第三方工具，以嵌入并拓展自身研究工作。 在当前发布版本中，GME工具包支持行业层面的泊松伪极大似然估计（Poisson Pseudo-Maximum Likelihood, PPML），并内置全部必要的诊断检验功能。本工具包还集成了一套用于生成描述性统计量及其他常见需求的信息分析工具。用户可选择完整保存或加载估计结果，亦可启用节省存储空间的轻量化结果模式。